The invention relates to an antiskid device for motor vehicle tires with an inner fastening or mounting engaging with the inside of the tire and with the inner fastening or mounting for chain strand portions extending over the tire tread, in which in the fitted state, the inner fastening has an approximately circular construction and has a central fastening section, to each of whose two ends is swivellably fixed a side part by means of a swivel joint and for fitting the inner fastening, the side parts can be opened outwards from the central fastening section and are in each case pretensioned by means of a spring device in the direction of a closed form of the inner fastening.
In the case of an antiskid chain of the aforementioned type, very easy fitting and completely uncomplicated operation is possible. Thus, for fitting purposes, the fitter only has to grip with the hands the two side parts of the inner fastening and swivel them radially outwards with respect to the central part until the inner fastening can be passed over the tire tread. The fitter must now release the two side parts, after which they are automatically swung into the position of the closed fastening on the inside of the tire, where they continue to be held under a given pretension.
However, it has been found that during the construction of the known antiskid chain with only a single rigid central part to which the side parts are fixed, particularly in the case of very small wheel cases and mudguards which are deep-seated relative to the tire, fitting can lead to certain difficulties, specifically when the rigid central part projects somewhat too far upwards after spreading apart the side parts and as a result of its given arcuate shape. In the case of large vehicles, where the wheel case have sufficient space, this has virtually no disadvantageous effects during fitting. However, in the case of small vehicles where the wheel cases are relatively small and narrow, fitting impediments can be caused.